As the market recognises the numerous benefits of dry-type transformers, specialist supplier Trafo Power Solutions has, in recent months, provided custom-designed units for a range of applications within South Africa and in other parts of the continent.
According to Trafo Power Solutions managing director, David Claassen, an increasingly popular application for their transformers has been in large industrial companies which leverage solar power to augment their energy needs during daylight hours.
“Where companies have the roof or ground space to accommodate photovoltaic cells, many are taking advantage of solar power to reduce consumption from Eskom and cut their monthly electricity bill,” says Claassen.
“With our experience in supplying the necessary specialised transformers for this purpose, we design and install units that are capable of supplying a 100% non-linear / inverter load while also providing electrostatic shielding between the medium voltage and low voltage sides of the transformer.”
Trafo Power Solutions recently installed and commissioned 1250 kVA and 1000 kVA units to serve large industrial bottling plants in Gauteng and Bloemfontein respectively
In another customised solution developed in response to a specific challenge faced by a customer, the company recently helped address the frequent voltage fluctuations in supply being experienced at the South African manufacturing facility of an international pharmaceutical company.
“Due to the instability of the electrical supply and frequent voltage fluctuations, it was decided the automatic on-load tap changer was the best solution for the customer,” he says. “We designed an integrated solution to automatically measure the supply voltage and change tap settings of the transformer in 9 steps of + and – 1,875% of on-load and without any interruption to the power supply feeding the facility.”
The supply and installation of two 1250 kVA transformers for this unique application was also completed in record time, including the commissioning and testing of the system within just three days of the units arriving from Hammond Power Solutions’ manufacturing facility in Italy.
There has also been steady demand for dry-type transformers in commercial buildings and hospitals, where users are looking to ensure high levels of safety in relatively confined spaces, while enjoying low maintenance requirements.
The absence of oil in the units gives them a higher safety rating than conventional oil-cooled transformers, and allows them to be installed indoors; users are also spared the cost of building special structures to accommodate the safety and environmental hazards related to oil-cooled units.
The upgrade of standby power generating facilities on two of the Johannesburg campuses of a leading South African university have also included four dry type transformers supplied by Trafo Power Solutions. The four transformers, two 2500 kVA and two 1000 kVA units, will step up the power supply from 400 V to 11 kV.
“We have also supplied numerous dry type lighting transformers for indoor and outdoor applications in the range of 25 kVA up to 200 kVA, as well as medium voltage outdoor potential transformers (PTs) or voltage transformers (VTs),” says Claassen. “These units are proving to be popular alternatives to the conventional oil-cooled transformer – due to their versatility in where they can be placed, and the avoidance of environmental risk.”